At Fault
by CaseyJ0nes
Summary: After their final encounter with Speed-Demon, Donnie admits to Casey about having been conscious throughout the whole ordeal. - Set directly after Race with a Demon.


**Alright, this story was requested by millin21 on tumblr, but I'm afraid I might have butchered Casey a bit. I always have the hardest time writing him, and it's even harder in a situation where he wouldn't necessarily act quite like his regular self. **

**Either way, I hope you all enjoy this little one-shot. **

* * *

They had drove back to the farm house in near silence, the only noise besides the old van itself being Mikey chattering about how amazing the entire experience had been.

Donnie had been especially quiet, while everyone would voice their opinions when Mikey asked, Donnie stayed quiet, only nodding his head his brother's way.

When they got back to the house Donnie had politely excused himself, giving Casey one more high five and a large smile for good measure before going back to his work bench.

It wasn't until a few hours after supper, when they noticed that Donnie had yet to come back in, did anyone think anything of it.

"If he doesn't come in soon I'll eat it." Mikey smiled happily.

"Mikey," Leo frowned.

"What? We don't want it to go bad." He gave a cheeky grin, before Raph rolled his eyes and punched him in the shoulder.

"Maybe someone should bring it out to him." Leo frowned, picking the plate up. "I hate it when he doesn't eat." He said quietly, though the room still heard him.

"I can do it." Casey offered, taking the plate from the eldest brother. "I was going to go work on the hot-rod, anyways."

"Did you just stop working on that thing?" April asked, raising an eyebrow.

"Yeah, but Don- uh, Speed Demon really did a number on it..." Casey said awkwardly, and then turned to the door.

April frowned as she watched him walk to the barn from the window.

"Yo, Don," Casey said as he entered the barn, looking over at Donnie's work bench where the turtle was currently hunched over.

Casey frowned when he didn't look up, instead continuing his work.

"Donnie?" He tried again, walking further in. "Donnie!" He shouted, and the mutant in question jumped, swinging his chair around.

"Casey," he said, shaking his head. "I didn't hear you."

"Whatever," the teen shrugged, then offered up the food. "I brought your supper.. The others were concerned when you didn't come to eat.."

"Oh, must have lost track of time." He said quietly, looking to the darkness outside the door, then back at the food.

Casey noted that his nose, or the part of his face where his nose should be, scrunched in disgust before he turned back around.

"You can just leave it there." He said, motioning to a clear spot near him on his work bench. Then he was back to work, mixing chemicals with some of the mutagen they had salvaged from the Kraang ship.

"So, uh, do you want to help me repair the hot-rod?" Casey asked, gesturing to the car and with a small smile on his face.

"No." Donnie said, keeping his eyes on his work.

"Well, do you need any help with what you're doing?" He tried again.

"No."

Casey frowned, taking a small step towards the mutant. "Dude, are you okay?"

"I'm _fine._" He said, but Casey's frown deepened.

"You don't look fine.."

Donnie paused whatever he was doing, reaching one hand to rub his eyes before turning his head to look at Casey.

"I almost killed you." He let out suddenly.

"_Oh_." Casey frowned. "You remembered that.."

"I remember it all." Donnie sighed. "I was conscious every, _single_ moment. Like- Like I was trapped inside my own body and I couldn't do anything! I couldn't move, I couldn't speak, I couldn't stop!" He slammed his hands on the table, and for the first time Casey noticed he was shaking.

"Don, it wasn't your fault. You were possessed by that stupid car-mutant thing."

"_Of course it's my fault._" Donnie sneered, looking at Casey like he was an idiot. "It was _my_ mutagen, it was _my _stupid plan, and it was _me_ who almost got everyone _killed_."

Casey frowned again. Raph had told him, when they first started hanging out and he had asked about his brothers, that Donnie was guilty by nature. He thought since he was the smartest he should be able to make plans that don't have bad outcomes, that anything he thinks of should come out flawlessly.

Even if Raph hadn't told him that, it was easy enough to figure out on your own. In the little time that Casey had known the turtles before the Invasion, he had known about Donnie the least, just because he spent so much time in his lab trying to create a retro-mutagen for April's dad. A mutation that Raph had repeatedly stated was in no way Donnie's or anybody else's fault but the Kraang. But Donnie took on all the guilt.

"Don, it's really not your fault." Casey told him, walking forwards to place a hand on his shoulder. "Your plan worked fine, it went down flawlessly. We just didn't know who the actual mutant was. If we had been right, and it had been the driver, than everything would have worked."

Donnie looked like he was going to say something, but Casey cut him off.

"And don't even start with that 'I should have known' crap. There was no way we could have known. End of story."

Donnie looked away, "I don't feel like the end of the story."

It was clear that Donnie was shaken from the event, but Casey wouldn't believe it if he wasn't, knowing that he remembered everything.

In an unusual show of affection, Casey reached forwards, enveloping Donnie in a tight hug. "Listen to me, it was _not your fault_."

It took Donnie a moment of shock before he returned the hug, only for a moment before stepping away.

"Thanks, Casey." Donnie gave a small shrug.

"No problem, Don." He said, then they were left in an awkward silence.

Casey cleared his throat, before swinging a hand out to punch Donnie in the arm. "Now, why don't we, um, fix the car, or something.." He suggested, and Donnie shook his head, giving a small laugh. "Huh, Alpaca-Face?"

"Yeah, sure, whatever, Behemoth." Donnie rolled his eyes, grabbing his tool-box from under his work bench.

* * *

**Okay, I hope it was well. **

**As always, you can send requests for me through a pm here, or a review, or on tumblr. My url is Caseyj0nes, with a zero instead of the o. **

**Please, review if you like it. Or even if you don't. **

**Byyyye~**


End file.
